272 
AMERICAN AG-RIC URTURIST. 
[July, 
TOYS & iHTOS’ (B©CTMMSo 
T!ie Woctor’s Talks. 
In our talks about the “Properties of Matter” last 
month we did not get through with them all. It did not 
need much illustration to show that size was a property 
or quality that belonged to all matter. Then there was 
Impenetrability , a long word to express the fact that no 
two bodies , or portions of matter could occupy the same 
space at the same time. Then there came the fact that 
matter can be divided— divisibility is the name for this 
property, and it was stated that there could be no portion 
of matter so small but we could not conceive that it may 
be smaller. Most of the illustrations showing the great 
extent to which matter can be divided, are from the 
solution of different substances in water. One of the 
bitterest of known tilings is 
THE POISON, STRYCHNINE. 
This is a white substance, looking much like salt; it is 
extracted from Nux-vomica , which is the seed of a small 
tree that grows in the East Indies. It is found that a 
single grain of this, dissolved in 1,750,000 grains of water, 
will make that water distinctly bitter to the taste, and 
we may infer that every grain of that water contains the 
1,750,000th of a grain of Strychnine. Some of the newly 
discovered coloring substances will color a large body of 
water, showing a still greater divisibility than Ibis. You 
have all blown soap-bubbles. I have often thought what 
a wonder a soap-bubble would be, if it could be produced 
only with great difficulty by means of costly apparatus in 
the hands of a person of great skill. But a clay pipe that 
costs but a cent, and a bit of soap, allows every child to 
produce one of the most wonderful and beautiful things 
in the world. Yes, 
EVERY SOAP-BUBBLE IS A WONDER. 
As yon blow, the bubble grows larger and larger; then 
come the colors, the tints of the rainbow, brighter and 
brighter; you will have them brighter and your bubble 
larger still—paff! where is the beautiful thing—surely 
not a “joy forever.” Well, so great a philosopher as 
Newton, found not only pleasure, but instruction in a 
soap-bubble. lie calculated—and if lie was wrong, we 
can not prove it—that the thickness (or thinness (?) of the 
film of the bubble just at the time of breaking, is the 
2,600,000th of an inch ! But the bubble is not all water. 
Every particle of the bubble contains some soap, one 
part of soap in one hundred parts of water will make good 
bubbles, hence it follows tiiat in every 2,600,000th of a 
cubic inch of film, one hundredth of it must be soap. 
This takes us into big figures, as one hundredth of the 
2,GOO,OOOtli of a cubic inch is Vi 7 , 576 >ooo,ooo>ooo trillionthof 
a cubic inch. More than that,every particle of this soap con¬ 
sists of four different elements, and if we should undertake 
to show how much of each of these was present in each 
2,600,000th of our cubic inch of film, we should get into 
figures quite beyond our conception—into the trillionths. 
HOW MUCH IS A TRILLIONTH ? 
To put the figures upon paper does not give any definite 
idea of the immensity of the sum. One writer tries to 
convey an idea of a trillionth in this way. Taking the 
accepted date of the creation of Adam, and supposing him 
to have counted one each second of time, and to have 
kept at it up to the present date (no allowance for sleep, 
sickness, or Sundays), he would not have made a large 
hole in a trillion ; suppose he had had Eve to help him, 
and the two had gone on counting one each second, they 
wonld be counting now with a fair prospect of having 
told off their trillion in the year 11800, or 10,000 years to 
come.—A trillion is a good many! But this illustration 
is only to show how excessively divided the soap must 
be in the 2,GOO,000th of a cubic inch of soap-bubble film. 
We have dwelt quite long enough on this property of 
matter. The next we notice is Porosity. Yon know tiiat 
a piece of bread or a brick is porous, that is, minute 
openings, or “ pores,” are found all through these and 
many other substances, but this is not the kind of porosity 
I would talk about, and this brings us to the interior 
structure of matter. Some illustrations of the extent to 
which matter may be divided have been given, but it is 
now generally believed by philosophers that however 
much we may divide matter, there is a point beyond 
which division is no longer possible, and that all matter 
is made up of particles so small that no human eye, with 
the most powerful of microscopes, has ever seen them, 
yet there seems to be no doubt that such exist, and they 
ARE CALLED ATOMS. 
This word atom is from the Greek words, meaning that 
which can not be cut, or divided—the ultimate particles 
of matter. How exceedingly minute these must be what 
I have said on divisibility shows. Another term is also 
nsed in speaking of matter, molecule , meaning a tiny 
mass. A molecule may consist of two or more atoms— 
thus a molecule of salt consists of an atom each of 
Chlorine and sodium. While it can not be proved, it is 
supposed that the atoms of matter are minute globes or 
spheres, and that these do not. quite touch one another, 
but have spaces between them. This is inferred from 
other properties of matter, but more especially from 
COMPRESSIBILITY'. 
There is no form of matter, so far as known, tiiat can 
not be made, by pressure, to take up less space than at 
first, and we shall see by and by that there are other 
reasons for thinking that there is space between the 
atoms of all matter, however solid it may seem to be. 
But I have already given you enough to think over. I)o 
not be impatient, I shall get to the experiments in due 
time. I wish you to think carefully over this and the 
last talk, for we are now building our foundation slowly, 
and the structure will go up more rapidly when that is laid. 
Tlie Fourth of July. 
How many of you have asked your friends these few 
days past, “What are you going to do on the 4th”?— 
Among boys there is but one 4th, and that is the fourth 
day of the present month. Every boy thinks he must 
do something on the 4th, and he begins to think of it 
days and weeks beforehand. He must not only do some¬ 
thing, but that something must be different from what 
ho will or can do on other days, or other holidays. Well 
what are you intending to do ? Why should you do any¬ 
thing on that day, any more than on the 3rd or 5th day 
of the month ? Perhaps you would find it difficult to 
answer this—and in that you would not he behind many 
older people, who would perhaps answer; “ to celebrate 
the day,” but if asked why it should be celebrated, would 
be puzzled for an answer. It will make a good beginning 
for a celebration for all hands, girls as well as boys, to 
find out, if they do not already understand it, why this 
particular day is to be celebrated. No doubt that many 
of you. the older youngsters, know that it is the day on 
which the Declaration op Independence was made. 
Independence of what? And why was it made? Get out 
your history or whatever book will tell the story, and in 
the cool of the morning, make these points quite clear. 
Then what is the Declaration ? This should be read 
on every 4th of July, at least. The reading of the 
Declaration will make a capital celebration of itself. 
Let the youngsters of the family, or of the neighborhood 
do that, whatever else is left undone. Then for the rest 
of the day, there are so many of you that we can not so 
well tell you what to do, as what not to do. In the first 
place, don’t get overheated, but keep cool, and avoid 
whatever will make you tired and cross before night 
comes. Don’t fire pistols, guns, or cannon, or any¬ 
thing of the kind. The list of so-called accidents from 
these is a sad one, don’t add to it. Don’t use fire¬ 
crackers—some won’t heed this. Many have saved their 
pocket-money to buy these snapping torments, and think 
there can bo no sort of a 4th of July without crackers. 
If you have bought them, the best way is to get rid of 
them as soon as possible.—Don’t fire them near the road 
to frighten horses, don’t fire them anywhere near the 
buildings or hay or straw stacks, but go where they can 
do no possible harm. As to those horrors called squibs 
or serpents, they have caused many a death—have noth¬ 
ing to do with them. Do nothing that can injure person 
or property. Enjoy all you can in a sensible manner. 
Sing, shout, play games, have a pic-nic—but we were 
not to tell you what to do. Do nothing that will make 
you wish that you had left it undone, and may you all 
have a pleasant day, and arise refreshed on the 5th. 
Tlie Woctor’s Correspondence. 
You youngsters who feel impatient that your letters 
are not answered “right eff,” “soon,” “by return mail,” 
must remember what I have already assured you more 
than once—that no inquiry is lost or overlooked, but 
there is good reason for the delay, and iu time an 
answer will come in the paper or by mail. 
those letters by mail, 
what a number there have been of late, and what an 
amount of time they have taken! Still I don’t think it 
right, to occupy space by a reply that interests just one 
person, so I answer such questions, when answerable, by 
mail—I say “ when answerable,” because many of them 
can not be answered by any living person. I can not 
now tell what these questions are, but each of you, if you 
do not find an answer here, or by mail, may know that 
you have put one of those conundrums to which there is 
no answer... .Here is one boy who wishes to know 
“about gas and how it is made.” 
He does not seem to know that there is a vast number 
of gases, all made differently, but by the next question, 
asking “how to make a balloon,” I infer that he has iu 
mind one of . the gases used to fill balloons. In places 
where gas is used for lighting, the street-gas is used to 
fill balloons, which must be very large. To make the gas 
used to fill small oiled silk balloons is an expensive and 
dangerous process, and not to be advised for boys. 
Almost any ingenious boy can make and 6end up 
A HOT-AIR BALLOON, 
and I will try at another time to tell you how this is done. 
... Here is Master J. W. S., who must be a new comer to 
our family, as he does not know that we always expect 
the full name. I overlook it this once. He wished to 
get some Chloroform to kill butterflies with, and the 
druggist would not let him have it. No doubt the drug¬ 
gist followed the law, as Chloroform, being sometimes 
put to improper uses, is classed among dangerous things, 
and not to be sold to every one. He would sell it to your 
father or other well known grown person, or you can go 
to your family physician, tell him the use to which you 
will put it, and, if he is a good-natured Doctor—most 
Doctors are good-natured—and knows you well, he will 
no doubt give you a prescription for it, and the druggist 
will then furnish it — Here is the father, “G. P.,” of 
one of our boys who wishes to know about something 
that may interest the boys also: “What is meant by 
THE TEMPER IN METALS ? ” 
The term temper is used very loosely, but to temper a 
metal really means to regulate its hardness, and the 
“ temper ” of a metal refers to its hardness and elastici¬ 
ty. Take, for example, steel, which is the most fre¬ 
quently tempered. If you have a steel rod and heat it 
bright red, and then suddenly plunge it into water, the 
steel will become very hard and brittle; if the water is 
ice-water it will be all the harder. Such steel may be 
ground to a very fine edge, but if you undertake to bend 
it, it will break like a pipe-stem. Take a bar thus treat¬ 
ed and made brittle, heat it red-hot, and allow it to cool 
slowly in the air. and it may be twisted into a kuot with¬ 
out breaking, but if made into an edge-tool it will be so 
soft that it will soon become dull. Now, between these 
two states—very hard and brittle and very soft and yield¬ 
ing—there is every degree, and to bring the steel (or other 
metal) into the proper condition for the use to be made 
of it, it is to be “ tempered,” that is, the hard and brittle 
steel has its hardness reduced and it is brought to the 
desired hardness or “ temper,” and this is done entirely 
by peculiar methods of heating and cooling, each work¬ 
man having his little trade secrets for accomplishing this. 
To “ temper” a metal is to bring it to the hardness re¬ 
quired for a particular purpose “J.B.,” Decorah, Iowa, 
has lost a Canary, a good singer, through the attacks of 
LITTLE RED LICE. 
He put some of these under his American Agriculturist 
Microscope, and saw what seemed like “big red crabs.” 
He wishes to know what will get rid of these and not in¬ 
jure the bird. I once knew an old German who kept 
many Canaries, and had great success with them. He 
had a fine strain of capital singers, and made considera¬ 
ble money by raising and selling the birds. I noticed 
that for each breeding cage he had a piece of Canton or 
cotton-flannel, and this he put on the cage at night, the 
fuzzy side down. I asked what this was for, and he told 
me that the lice would gather in these pieces of flannel, 
and in the morning he would scald the cloths to kill the 
lice, dry them, and have them all ready to be put on 
again at night. This is very simple and easily tried. 
Allowing the birds to bathe frequently, and mixing a 
little auiseed with the gravel on the floor, are said by 
the books on birds to be the best preventives of lice. 
